Circuit Switching

networking

Definition

Circuit Switching

Let $N=(V,E)$ be a computer network with nodes $V$ and links $E$.

Circuit switching is a data transmission method in which a dedicated communication path — a circuit — is established between a source $s\in V$ and a destination $t\in V$ before any data transfer begins. The circuit reserves link capacity exclusively for the duration of the session.

Formally, a circuit is a path $P\subseteq E$ from $s$ to $t$ where each $e\in P$ allocates a fixed portion of its capacity to the session. Data flows along $P$ without per-unit routing decisions.